Furnace



No. 625,402. Patented may 23, |899. n. H. LENTz.

FU RNCE.

(Application -led Nov. 22, 1897.) (No Model.)

NTTED STATES PATENT OFFICE.

DAVID II. LENTZ, OF JOLIET, ILLINOIS, ASSIGNOR TO THE MCKENNA STEEL VORKING COMPANY, OF MILWAUKEE, \VISOOI\ISINA FU RNAC E.

SPECIFICATION forming part of Letters Patent No. 625,402, dated May 23, 1.899.

Application filed NOvember 22, 1897. Serial N0. 659,478. (No model.)

To all whom it may concern:

Be it known that I, DAVID H. LENTZ, acitizen of the United States, residing at Joliet, in the county of Vill and State of Illinois,have invented a certain new and useful Improvement in Furnaces, (Oase No. 1,) of which the following is a full, clear, concise, and exact description, reference being had to the 'accompanying drawings,formingapart ofthisspeci- 1o tication.

My invention relates to improvements in reverberatory furnaces, and has for its object the production of means for securing more efficient and equable heating throughout the heating-chamber of a furnace.

My invention is more particularly applicable to a reverberatory furnace for evenly heating large objects, such as railroad-rails, and my said invention will be described in conzo nection with a furnace of this class.

Hitherto heating-furnaces have been constructed wherein the 'treated metal of small bulk could be evenly heated throughout its mass; but such furnaces when constructed 2 5 upon a large scale were not capable of evenly heating railroad-rails throughout their entire length, which is necessary when the same require rerolling or being otherwise worked in a heated condition. As the standard length 3o of railroad-rails is thirty feet, it has accordingly been my purpose to devise a furnace of large proportions which, however, would be capable of economically producing and maintaining in all portions of its heating-chamber 3 5 a uniform or substantially uniform temperature. This I have been able to attain by the construction herewith shown and described, in connection with which I will set forth the features of my invention, which will be more 4o readily comprehended by reference to the accompanying drawings, wherein- Figure l is a plan view of the furnace in section. Fig. 2 is a vertical sectional view thereof on line 2 2 of Fig. l. Fig. 3 is another vertical section on line 3 3 of Fig. l. Fig. et is a similar view on line -iL 4 of Fig. l.

The same letter of reference is u sed throughout the several figures to designate similar parts.

5o The furnace is provided with two fire-boxes or combustion-chambers a, situated upon one side and near the ends of the heating-chamber b. Doors a are provided, through which the fuel employed is passed to the hearths a2. The rear hearth-wall a3 extends slightly above 5 5 the doors a'. The tlues a4, affording communication between the nre-boxes and the heating-chamber, extend the entire length of said lire-boxes, before which fire-bridges c are disposed within the heating-chamber and extend 6o considerably beyond the flue a4 at a diagonal with the hearth-wall. The fire-bridges are slightly separated from the hearth-Walls and extend centrally almost to the top of the flueopenings a4, sloping away at either end, asis most clearly shown in Fig. 2. Centrally disposed withinthe heatingchamber and extending across the same from side to side in the' position of greatest rise of its upwardly-sloping roof is provided the iire- 7o arch d. (Shown in Figs. 3 and 4.) The archopening rises a short distance above the charging-floor cl, whereon the rails are placed for heating Within the chamber o. The firearch is adapted to direct downwardly and lat- 7 5 erally the currents of name and heated gases entering said chamber through the fine-openings after their dispersion by the fire-bridges and their expansion within the heatingchamber. At eitherend of the heating-cham- 8o ber are the charging gates or openings f, through which the said rails 0r other product to be treated are passed'to the interior of said heating-chamber. Doors or slides g are hung before said openings and adapted to be simultaneously operated by means of the connected bell-crank arms g', from which the said doors are hung. Oounterweight g2 is provided upon one of said bell-crank arms t'o balance the weight of the doors or slides. 9o

As shown more clearly in Fig. 3, the heat-- ing-chamber is connectedwith the chimneystack h through the fines c' c", provided at either side of said chamber beneath the ends of the fire-arch d. Flue t" connects with the said chimney-stack through the underdraftue i2, passing beneath the iioor of the heating-chamber. Dampers k 7c are situated in flues i 11,' respectively. I have shown, somewhat diagrammatically, in the chimney-stack roo the foundation and lower portion of a Watertube boiler, which, however, form no part of my present invention and will require no description in this specification. The fire-boxes are providedwith both hot and cold blast, the

supply-pipes Z being connected with a sourceA of air under pressure and extending to the twyers m and n, which are respectively controlled by the valves m and n. The supplypipes for the twyers ot extend through the Walls of the fire-boxes d, whereby the air is heated before being forced within the combustion-chamber.

The operation of the furnace of my invention is as follows: The slides g being raised, the rails are slid into position upon the floor of the heating-chamber and the slides are immediately closed. The blast is turned on the fire-boxes, the proportion of the hot and cold blast being so adjusted as to drive the flame and heated gases with the assistance of the tire-bridges and fire-arch as equally as possible throughout the heating-chamber. As the heat increases within the chamber the operators in charge of said furnace adjust the valves mi and at of the blast, as well as the dampers k 7.3', so as to rectify any underheating or overheating liable to occur in any portion of the chamber. As is well known, the combustion prod uced by a hot blast is violent and accompanied by little yflame but very intense heat, Whereas that produced by a cold blast is lnore gradual, while the fiame is very greatly increased, and thus by adjusting the valvesv controlling the blasts the operators may generally direct the heating in any portion of the chamber. In addition by opening and closing the dampers Zo 7c' to a greater or less degree the passage of the heated gases and flame is controlled. Thus the flames are driven over the fire-brid ges, which spread the same, as indicated by the arrows in the several figures, passing to the various portions of the heating-chamber, and finally are directed downward centrally in said chamber beneath the fire-arch to the flues i t, from which exit is had to t-he chimney-stack. The fire-arch and fire-bridges serve to maintain the heated gases within the chamber for a considerable length of time, so that a large percentage of the heat is utilized, and thus by controlling the said heating through the several means indicated the rails or other treated product are evenly heated throughout When this is attained, the slides before the charginggates are thrown open and the heated rails may bel removed from one end of the furnace while others are being placed within the heating-chamber at the other end. Thus the furnace is capable of being rapidly operated at its full capacity.

It is apparent that alterations may be made in the structure herein shown and described, as indicated in the accompanying claims, without departing from the spirit of' my invention, and I accordingly desire to secure, together with all such modifications, the following:

1. The combination in a furnace, with a heating-chamber, of a fire-box, a communieating flue connecting the said fire-box and heating-chamber, and a tire-bridge disposed before the said flue, the said bridge extending approximately to the top of the central portion of the flue-openingaud sloping downwardly at either end and adapted to direct the flame and heated gases upwardly and laterally within the heating-chamber, whereby an equal temperature is maintained in the diiferent portions thereof, substantially as described.

2. The combination in a reverberatory furnace, with a heating-chamber, of a fire-box or combustion-chamber associated therewith, a flue-opening affording' communication between said heating-chamber and hre-box, means for supplying an air-blast to the said fire-box, and a lire-bridge disposed before the flue-opening extending centrally to the approximate height of the opening, the safebridge sloping downwardly at either end thereof, whereby the fiame and heated gases from the fire-box are distributed throughout the heating chamber, substantially as described.

3. The combination in a furnace of the class described, with aheati-ng-chamber, of a firebox'or combustion-chamber associated therewith, a flue-opening affording communication between the said chambers, a second iiue opening affording communication with the chimney-stack of thefurn ace,and a tire-bridge disposed before the said flue-opening extending diagonally and sloping downwardly therefrom adapted to direct the flames and heated gases in the general direction of the second- `named flue-opening, substantially as described.

Li. In a reverberatory furnace, the combi- Vnation with a heating-chamber, of a fire-box,

a communicating iiue connecting thesaid firebox and heating-chamber, and a fire-bridge disposed before the said iiue, the said bridge extending approximately to the top of the central portion of the fine-opening and sloping downwardly at either end, whereby the fiame and heated gases from the said fire-box are distributed throughout the heating-chamber, substantially as described. their entire mass to the desired temperature.

5. The combination in a furnace, with a heating-chamber, of a fire-box or combustionchamber associated therewith and` opening linto said heating-chamber, a fire-arch situ- 1 ated within said heating-chamber, and a flue opening or openings communicating with the chimney-stack of the furnace disposed beneath and at the ends of the said fire-arch,

l.adapted to direct the heated gases and flame within the chamber downwardly and laterlTally to the said chimney-stack, substantially as described.

IOO

IIO

G. In a reverberatory furnace, the combination with a heating-chamber, and a firebox or combustion-chamber associated therewith, of means for supplying an air-blast to said combustion-chamber, a flue affording communication between the said fire-box and heating-chamber, a fire-bridge disposed before the flue, a fire-arch situated within the heating-chamber, and flues disposed at the bottom of said heating-chamber beneath and at the ends of the arch, whereby the heated gases and flames entering by way of the flue are directed throughout the chamber to secure an equal temperature therein, substantially as described.

7. In a reverberatory furnace, the combination with a heating-chamber, of fire-boxes associated therewith and near each end thereof, means for supplying an air-blast to said hre-boxes, flues affording communication between the said fire-boxes and heating-chamber, tire-bridges disposed before the flues, a lire-arch centrally situated within the heatingchamber, flues disposed at each side of the bottom of the heating-chamber and communicating with the chimney-stack, and means for controlling the passage of the heated gases through said iues, substantially as described.

8. In a furnace of the class described, the combination with aheating-chamberh,of fireboXes a disposed upon a side and near the ends of said heating-chamber, communicating ilues a" fire-bridges c c arranged before the communicating ilues of said fire-boxes, a fire-arch d centrally disposed within said heating-chamber, and flues 2' t" disposed beneath said fire-arch at each side of the chamber and affording communication with the chimney-stackjof the furnace, substantially as described.

9. In a furnace, the combination with reboxes a ct, of means for supplying and controlling hot and cold blasts within the said fire-boxes, a heating-chamber b near the ends of which the said {ire-boxes are situated,com municating ues a4, fire-bridges c disposed before said fiues, a fire-arch d disposed in the heating chamber between the said firebridges, and flues i t" situated at the base of the fire-arch at each side of the chamber and communicating with the chimney-stack of the furnace, substantially as described.

l0. In a furnace of the class described, the combination with 'a nre-box or combustionchamber, of a heating-chamber communicat-- 

